表操作练习题：
- 练习：用户表，用户组表，主机表，业务线表
- 关联：用户与用户组 主机与业务线 用户与主机
# 用户表 create table user( id int not null unique auto_increment, username varchar(20) not null, password varchar(50) not null, primary key(username,password) ); insert into user(username,password) values ('root','123'), ('egon','456'), ('alex','alex3714') ; mysql> desc user; +----------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | UNI | NULL | auto_increment | | username | varchar(20) | NO | PRI | NULL | | | password | varchar(50) | NO | PRI | NULL | | +----------+-------------+------+-----+---------+----------------+ rows in set (0.00 sec) mysql> select * from user; +----+----------+----------+ | id | username | password | +----+----------+----------+ | 1 | root | 123 | | 2 | egon | 456 | | 3 | alex | alex3714 | +----+----------+----------+ rows in set (0.00 sec) # 用户组表 create table usergroup( id int primary key auto_increment, groupname varchar(20) not null unique ); insert into usergroup(groupname) values ('IT'), ('Sale'), ('Finance'), ('Boss') ; mysql> desc usergroup; +-----------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | groupname | varchar(20) | NO | UNI | NULL | | +-----------+-------------+------+-----+---------+----------------+ rows in set (0.00 sec) mysql> select * from usergroup; +----+-----------+ | id | groupname | +----+-----------+ | 4 | Boss | | 3 | Finance | | 1 | IT | | 2 | Sale | +----+-----------+ rows in set (0.01 sec) # 主机表 create table host( id int primary key auto_increment, ip char(15) not null unique default '127.0.0.1' ); insert into host(ip) values ('172.16.45.2'), ('172.16.31.10'), ('172.16.45.3'), ('172.16.31.11'), ('172.10.45.3'), ('172.10.45.4'), ('172.10.45.5'), ('192.168.1.20'), ('192.168.1.21'), ('192.168.1.22'), ('192.168.2.23'), ('192.168.2.223'), ('192.168.2.24'), ('192.168.3.22'), ('192.168.3.23'), ('192.168.3.24') ; mysql> desc host; +-------+----------+------+-----+-----------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+----------+------+-----+-----------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | ip | char(15) | NO | UNI | 127.0.0.1 | | +-------+----------+------+-----+-----------+----------------+ rows in set (0.00 sec) mysql> select * from host; +----+---------------+ | id | ip | +----+---------------+ | 5 | 172.10.45.3 | | 6 | 172.10.45.4 | | 7 | 172.10.45.5 | | 2 | 172.16.31.10 | | 4 | 172.16.31.11 | | 1 | 172.16.45.2 | | 3 | 172.16.45.3 | | 8 | 192.168.1.20 | | 9 | 192.168.1.21 | | 10 | 192.168.1.22 | | 12 | 192.168.2.223 | | 11 | 192.168.2.23 | | 13 | 192.168.2.24 | | 14 | 192.168.3.22 | | 15 | 192.168.3.23 | | 16 | 192.168.3.24 | +----+---------------+ rows in set (0.01 sec) # 业务线表 create table business( id int primary key auto_increment, business varchar(20) not null unique ); insert into business(business) values ('轻松贷'), ('随便花'), ('大富翁'), ('穷一生') ; mysql> desc business; +----------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | business | varchar(20) | NO | UNI | NULL | | +----------+-------------+------+-----+---------+----------------+ rows in set (0.00 sec) mysql> select * from business; +----+-----------+ | id | business | +----+-----------+ | 3 | 大富翁 | | 4 | 穷一生 | | 1 | 轻松贷 | | 2 | 随便花 | +----+-----------+ rows in set (0.00 sec) # 建关系 user usergroup create table user2usergroup( id int not null unique auto_increment , user_id int not null, group_id int not null, primary key(user_id,group_id), foreign key(user_id) references user(id) on delete cascade on update cascade, foreign key(group_id) references usergroup(id) on delete cascade on update cascade ); insert into user2usergroup(user_id,group_id) values (1,1), (1,2), (1,3), (1,4), (2,3), (2,4), (3,4) ; mysql> desc user2usergroup; +----------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+---------+------+-----+---------+----------------+ | id | int(11) | NO | UNI | NULL | auto_increment | | user_id | int(11) | NO | PRI | NULL | | | group_id | int(11) | NO | PRI | NULL | | +----------+---------+------+-----+---------+----------------+ rows in set (0.00 sec) mysql> select * from user2usergroup; +----+---------+----------+ | id | user_id | group_id | +----+---------+----------+ | 1 | 1 | 1 | | 2 | 1 | 2 | | 3 | 1 | 3 | | 4 | 1 | 4 | | 5 | 2 | 3 | | 6 | 2 | 4 | | 7 | 3 | 4 | +----+---------+----------+ rows in set (0.00 sec) # 建关系 host business create table host2business( id int not null unique auto_increment, host_id int not null, business_id int not null, primary key(host_id,business_id), foreign key(host_id) references host(id) on delete cascade on update cascade, foreign key(business_id) references business(id) on delete cascade on update cascade ); insert into host2business(host_id,business_id) values (1,1), (1,2), (1,3), (2,2), (2,3), (3,4) ; mysql> desc host2business; +-------------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+---------+------+-----+---------+----------------+ | id | int(11) | NO | UNI | NULL | auto_increment | | host_id | int(11) | NO | PRI | NULL | | | business_id | int(11) | NO | PRI | NULL | | +-------------+---------+------+-----+---------+----------------+ rows in set (0.00 sec) mysql> select * from host2business; +----+---------+-------------+ | id | host_id | business_id | +----+---------+-------------+ | 1 | 1 | 1 | | 2 | 1 | 2 | | 3 | 1 | 3 | | 4 | 2 | 2 | | 5 | 2 | 3 | | 6 | 3 | 4 | +----+---------+-------------+ rows in set (0.00 sec) # 建关系 user host create table user2host( id int not null unique auto_increment, user_id int not null, host_id int not null, primary key(user_id,host_id), foreign key(user_id) references user(id) on delete cascade on update cascade, foreign key(host_id) references host(id) on delete cascade on update cascade ); insert into user2host(user_id,host_id) values (1,1), (1,2), (1,3), (1,4), (1,5), (1,6), (1,7), (1,8), (1,9), (1,10), (1,11), (1,12), (1,13), (1,14), (1,15), (1,16), (2,2), (2,3), (2,4), (2,5), (3,10), (3,11), (3,12) ; mysql> desc user2host; +---------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +---------+---------+------+-----+---------+----------------+ | id | int(11) | NO | UNI | NULL | auto_increment | | user_id | int(11) | NO | PRI | NULL | | | host_id | int(11) | NO | PRI | NULL | | +---------+---------+------+-----+---------+----------------+ rows in set (0.00 sec) mysql> select * from user2host; +----+---------+---------+ | id | user_id | host_id | +----+---------+---------+ | 1 | 1 | 1 | | 2 | 1 | 2 | | 3 | 1 | 3 | | 4 | 1 | 4 | | 5 | 1 | 5 | | 6 | 1 | 6 | | 7 | 1 | 7 | | 8 | 1 | 8 | | 9 | 1 | 9 | | 10 | 1 | 10 | | 11 | 1 | 11 | | 12 | 1 | 12 | | 13 | 1 | 13 | | 14 | 1 | 14 | | 15 | 1 | 15 | | 16 | 1 | 16 | | 17 | 2 | 2 | | 18 | 2 | 3 | | 19 | 2 | 4 | | 20 | 2 | 5 | | 21 | 3 | 10 | | 22 | 3 | 11 | | 23 | 3 | 12 | +----+---------+---------+ rows in set (0.00 sec)